This paper explores how socio-economic, especially socio-religious affiliations, and demographic characteristics of individuals influence participation in higher education (HE). It argues that appropriate measures of 'deficits' in participation should inform the nature and scope of affirmative action. The analytical and policy relevance of distinguishing between stock and flow measures, the differences in eligibility for HE across groups are emphasized. After controlling for relevant factors, the 'hierarchy of participation in higher education' that emerges from detailed analysis suggests that deficits for some marginalized groups are not high enough to justify reservation for these groups on the basis of low participation.